Structural chemistry by diffraction methods
[CHM2251]
[22.5h + 7.5h] 3 credits
Teacher(s): Jean-Paul Declercq
Language: English
Level: Second
Aims
2. Application to small molecules and biological macromolecules.
Main themes
2. X-ray diffraction, theory and experimental methods.
3. Crystalline and molecular structures determination methods.
4. Interpretation of results.
Content and teaching methods
2. Manipulation of crystals, cryogenic set-ups, preparation of heavy atom derivatives.
3. Reminder of basic relations of X-ray crystallography.
4. Experimental methods applicable to monocrystals.
5. Determination of direct and reciprocal reticular parameters
6. Determination of space groups.
7. Measure of crystal diffracted intensities.
8. Lorentz, polarisation, absorption corrections
9. How to go from diffraction data to the structure: structural factors and electronic density, Fourier transform, phase problems. Wilson statistic.
10. Patterson function, direct methods, isomorphous replacement, anomalous scattering, MAD (multiwavelength anomalous dispersion) and SAD methods (single wavelength anomalous dispersion).
11. Determination and use of non crystallographic symmetry.
12. Refinement and phase extensions by modifying electronic density.
13. Molecular replacement, classic methods and methods based on the "likelihood maximum".
14. Refining of molecular structures.
15. Quality, analysis and interpretation of results.
Other information (prerequisite, evaluation (assessment methods), course materials recommended readings, ...)
Molecular symmetry and crystal structures (CHM 1251A)
Evaluation mode:
Oral exam with a written preparation
The course could be partly or totally delivered by an invited lecturer.